As methods for directly separating and analyzing enantiomer mixtures of compounds containing an asymmetric carbon atom using optically active compound-grafted packing materials by means of liquid chromatography, there have hitherto been only a few of reports, for example, a ligand exchange-method by Davankov et al. in which optically active proline-grafted packing materials are used; a charge transfer complex-method by Gil-Av et al. in which .pi.-electron-lacking and optically active compound-grafted packing materials are used; a method involving separation of N-acylated amino acid esters or N-acylated dipeptide esters using optically active N-acylated amino acid-grafted packing materials by Hara et al.; a method involving separation of 3,5-dinitrobenzoylated amino acids, amines, hydroxy acids, sulfoxides, etc. using optically active 1-(9-anthryl)trifluoroethanol-grafted packing materials, or a method involving separation of aromatic alcohols using 3,5-dinitrobenzoylated and optically active phenylglycine-grafted packing materials by Pirkle et al.; and so on. In these methods, however, compounds useful for analysis are limited to a narrow range, a degree of separation is poor, or grafted packing materials are produced with difficulty so that packing materials have good reproducibility in the quality, etc. It cannot thus be said that these packing materials are practical.